Transducer for generating optical contrasts

Abstract

A transducer in an imaging optical system for generating optical contrasts in the near-field representation of topographies of an object by outcoupling evanescent waves from the underside of the transducer. The transducer comprises a substrate having a transparent plane-parallel protuberance corresponding to the field size of the imaging optical system and pointing toward the object. The specimen outcouples evanescent waves from an underside of the transducer, where the transducer underside is arranged in a focal plane of the imaging optical system.

What is claimed is:  
     
       1. An imaging optical system for imaging an object, comprising: 
       a transducer comprising a substrate, the substrate having a transparent plane-parallel protuberance corresponding to a field size of the imaging optical system and pointing toward the object,  
       wherein the object outcouples evanescent waves from an underside of the transducer,  
       wherein the transducer underside is arranged in a focal plane of the imaging optical system, and  
       wherein the imaging optical system is configured to generate optical contrasts in the near-field representation of topographies of the object.  
     
     
       2. The imaging optical system as claimed in  claim 1 , wherein the imaging optical system comprises: 
       an objective of a reflective light microscope.  
     
     
       3. The imaging optical system as claimed in  claim 2 , further comprising: 
       a dark field beam path defined, in part, by a dark field stop arranged at an exit pupil plane of the imaging optical system.  
     
     
       4. The imaging optical system as claimed in  claim 1 , wherein the imaging optical system comprises an objective of an information write and/or read unit and wherein the object is an optical memory. 
     
     
       5. The imaging optical system as claimed in  claim 1 , wherein the transducer comprises a thin glass platelet substrate, and the protuberance is produced by thermal embossing. 
     
     
       6. The imaging optical system as claimed in  claim 1 , wherein a face of the protuberance includes a marking situated concentrically with its midpoint. 
     
     
       7. The imaging optical system as claimed in  claim 6 , wherein the marking is located on a face of the protuberance facing the object. 
     
     
       8. The imaging optical system as claimed in  claim 1 , wherein the transducer is optically coupled to an objective of the imaging optical system via an immersion. 
     
     
       9. The imaging optical system as claimed in  claim 8 , wherein the immersion comprises an oil. 
     
     
       10. The imaging optical system as claimed in  claim 8 , wherein the immersion comprises a material selected from the group consisting of a transparent elastic substance and a plastic substance. 
     
     
       11. The imaging optical system as claimed in  claim 1 , further comprising: 
       a layer applied to a face of the protuberance facing the object, wherein said layer comprises a uniformly thick, flat layer made from a material which has a higher refractive index than a refractive index of the protuberance.  
     
     
       12. The imaging optical system as claimed in  claim 11 , further comprising refractive or diffractive structures on the face of the protuberance facing the object in an edge region, wherein parallel light beams coming from the imaging optical system can be coupled into the layer with the higher refractive index. 
     
     
       13. The imaging optical system as claimed in  claim 1 , further comprising: 
       a layer applied to a face of the protuberance facing the object, wherein said layer comprises a material having a higher resistance to scratching than the protuberance.  
     
     
       14. The imaging optical system as claimed in  claim 1 , further comprising: 
       a thin-framed plate for holding the transducer.  
     
     
       15. The imaging optical system as claimed in  claim 14 , wherein the thin-framed plate is connected to the imaging optical system via an adjustable holder. 
     
     
       16. The imaging optical system as claimed in  claim 15 , wherein the adjustable holder permits an alignment of the protuberance in the focal plane of the imaging optical system. 
     
     
       17. The imaging optical system as claimed in  claim 1 , further comprising: 
       a partially transparent coating applied to a face of the protuberance facing the object, wherein the transparent coating is disposed in an edge region of the protuberance.  
     
     
       18. The imaging optical system as claimed in  claim 1 , further comprising: 
       a linear grating structure disposed on a face of the protuberance facing the object.  
     
     
       19. The imaging optical system as claimed in  claim 1 , further comprising: 
       an array of active light sources disposed on a face of the protuberance facing the object.  
     
     
       20. The imaging optical system as claimed in  claim 1 , further comprising: 
       a dot structure arranged in grating-form disposed on a face of the protuberance facing the object, wherein dots forming the dot structure have lateral dimensions below a resolving power of the imaging optical system, and wherein the dots comprise a fluorescing material.  
     
     
       21. The imaging optical system as claimed in  claim 1 , further comprising: 
       a point stop structure arranged in the form of a grating disposed on a face of the protuberance facing the object, wherein stop holes comprising the point stop structure have lateral dimensions below the resolving power of the imaging optical system, and wherein the stop holes are arranged as light exit openings and light entry openings for a near-field representation of the topography of the object.  
     
     
       22. The imaging optical system as claimed in  claim 1 , further comprising: 
       electrically conducting layers structured by fine dividing lines to form electric capacitors from suitable contact between two respectively associated regions electrically insulated from one another that are disposed in an edge region on a face of the protuberance facing the object.  
     
     
       23. The imaging optical system as claimed in  claim 1 , further comprising: 
       electrically conducting layers structured by fine dividing lines to form electric capacitors from suitable contact between two respectively associated regions electrically insulated from one another that are disposed in an edge region on a face of the protuberance facing an objective of the optical imaging system.  
     
     
       24. The imaging optical system as claimed in  claim 1 , further comprising: 
       an opaque layer, applied in an edge region to a face of the protuberance facing the object, having a plurality of windows situated symmetrically relative to one another for light exit and light entry.  
     
     
       25. The imaging optical system as claimed in  claim 1 , further comprising: 
       an objective.  
     
     
       26. The imaging optical system of  claim 25 , further comprising: 
       a grating structure disposed on a face of the protuberance facing the object; and an illuminating beam defined by a light source and an illuminated field stop having a plurality of openings, wherein an arrangement of said plurality of openings correspond to and are imageable onto the grating structure.  
     
     
       27. The imaging optical system as claimed in  claim 1 , wherein the transducer is optically coupled to an objective of the imaging optical system via a flexible immersion. 
     
     
       28. The imaging optical system as claimed in  claim 27 , wherein the flexible immersion comprises an oil. 
     
     
       29. The imaging optical system as claimed in  claim 27 , wherein the flexible immersion comprises a material selected from the group consisting of a transparent elastic substance and a plastic substance. 
     
     
       30. The imaging optical system as in  claim 1 , wherein said protuberance is integrally formed with said substrate. 
     
     
       31. The imaging optical system as in  claim 1 , wherein the imaging optical system is configured to generate said optical contrasts by measuring spatial intensities of the evanescent waves outcoupled by the object. 
     
     
       32. The imaging optical system as in  claim 31 , wherein the imaging optical system is a microscope configured to image a specimen. 
     
     
       33. A transducer, in an imaging optical system, for generating optical contrasts in the near-field representation of topographies of an object, comprising: 
       a substrate having a transparent plane-parallel protuberance corresponding to a field size of the imaging optical system and pointing toward the object, wherein the transducer outcouples evanescent waves from an underside of the transducer, wherein the transducer underside is arranged in a focal plane of the imaging optical system, and wherein a face of the protuberance comprises at least one of a grating structure, an array of quantum point lasers, a dot structure arranged in grating-form, and a point stop structure arranged in the form of a grating.  
     
     
       34. A transducer, in an imaging optical system, for generating optical contrasts in the near-field representation of topographies of an object, comprising: 
       a substrate having a transparent plane-parallel protuberance corresponding to a field size of the imaging optical system and pointing toward the object, wherein the transducer outcouples evanescent waves from an underside of the transducer, wherein the transducer underside is arranged in a focal plane of the imaging optical system, and wherein a face of the protuberance further comprises a layer applied thereon, wherein said layer comprises one of a material having a higher refractive index than a refractive index of the protuberance and a material having a higher resistance to scratching than the protuberance.  
     
     
       35. A transducer, in an imaging optical system, for generating optical contrasts in the near-field representation of topographies of an object, comprising: 
       a substrate having a transparent plane-parallel protuberance corresponding to a field size of the imaging optical system and pointing toward the object, wherein the transducer outcouples evanescent waves from an underside of the transducer, and wherein the transducer underside is arranged in a focal plane of the imaging optical system; and  
       electrically conducting layers structured by fine dividing lines to form electric capacitors from contact between two respectively associated regions electrically insulated from one another that are disposed in an edge region on a face of the protuberance facing one of the object and an objective of the optical imaging system.  
     
     
       36. A transducer, in an imaging optical system, for generating optical contrasts in the near-field representation of topographies of an object, comprising: 
       a substrate having a transparent plane-parallel protuberance corresponding to a field size of the imaging optical system and pointing toward the object, wherein the transducer outcouples evanescent waves from an underside of the transducer, and wherein the transducer underside is arranged in a focal plane of the imaging optical system; and  
       at least one of: a) a partially transparent coating applied to a face of the protuberance facing the object, wherein the transparent coating is disposed in an edge region of the protuberance; and b) an opaque layer, applied in an edge region to a face of the protuberance facing the object, having a plurality of windows situated symmetrically relative to one another for light exit and light entry.